## About

36

Publications

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236

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Introduction

My research activity deals mainly with the development and test of new methods for orbit propagation and determination of small Solar system bodies, and the study of their dynamics.

Additional affiliations

January 2016 - present

November 2012 - December 2015

December 2009 - September 2010

## Publications

Publications (36)

The concept of sphere of influence of a planet is useful in both the
context of impact monitoring of asteroids with the Earth and of
the design of interplanetary trajectories for spacecrafts. After
reviewing the classical results, we propose a new definition for this
sphere that depends on the position and velocity of the small body for
given value...

We investigate the behaviour of two recent methods for the computation of preliminary orbits. These methods are based on the conservation laws of Kepler’s problem, and enable the linkage of very short arcs of optical observations even when they are separated in time by a few years. Our analysis is performed using both synthetic and real data of 822...

The paper addresses the problem of minimizing the impact of non-linearities when dealing with uncertainty propagation in the perturbed two-body problem. The recently introduced generalized equinoctial orbital element set (GEqOE) is employed as a means to reduce non-linear effects stemming from J2 and higher order gravity field harmonics. The uncert...

We investigate the behaviour of two recent methods for the computation of preliminary orbits. These methods are based on the conservation laws of Kepler's problem, and enable the linkage of very short arcs of optical observations. Our analysis is performed using both synthetic and real data of 822 main belt asteroids. The differences between comput...

We investigate the planar motion of a mass particle in a force field defined by patching Kepler’s and Stark’s dynamics. This model is called Sun-shadow dynamics, referring to the motion of an Earth satellite perturbed by the solar radiation pressure and considering the Earth shadow effect. The existence of periodic orbits of brake type is proved, a...

We introduce six quantities that generalize the equinoctial orbital elements when some or all the perturbing forces that act on the propagated body are derived from a potential. Three of the elements define a non-osculating ellipse on the orbital plane, other two fix the orientation of the equinoctial reference frame, and the last allows us to dete...

Here, we revisit an initial orbit determination method introduced by O. F. Mossotti employing four geocentric sky-plane observations and a linear equation to compute the angular momentum of the observed body. We then extend the method to topocentric observations, yielding a quadratic equation for the angular momentum. The performance of the two ver...

We introduce six quantities that generalize the equinoctial orbital elements when some or all the perturbing forces that act on the propagated body are derived from a disturbing potential. Three of the elements define a non-osculating ellipse on the orbital plane, other two fix the orientation of the equinoctial reference frame, and the last allows...

Here we reprise an initial orbit determination method introduced by O. F. Mossotti employing four geocentric sky-plane observations and linear equations to compute the angular momentum of the observed body. We then extend the method to topocentric observations, yielding quadratic equations for the angular momentum. The performance of the two versio...

We investigate the planar motion of a mass particle in a force field defined by patching Kepler’s and Stark’s dynamics. This model is called Sun-shadow dynamics, referring to the motion of an Earth satellite perturbed by the solar radiation pressure and considering the Earth shadow effect. The existence of periodic orbits of brake type is proved, a...

We present a new method for computing orbits in the perturbed two-body problem: the position and velocity vectors of the propagated object in Cartesian coordinates are replaced by eight orbital elements, i.e., constants of the unperturbed motion. The proposed elements are uniformly valid for any value of the total energy. Their definition stems fro...

We present an alternative method for computing orbits in the perturbed two-body problem: the position and velocity vectors of the propagated object in Cartesian coordinates are replaced by eight orbital elements, i.e., constants of the unperturbed motion. The proposed elements are uniformly valid for any value of the total energy. Their definition...

This paper is concerned with the comparison of semi-analytical and non-averaged propagation methods for Earth satellite orbits. We analyse the total integration error for semi-analytical methods
and propose a novel decomposition into dynamical, model truncation, short-periodic, and numerical error components. The first three are attributable to dis...

This paper is concerned with the comparison of semi-analytical and non-averaged propagation methods for Earth satellite orbits. We analyse the total integration error for semi-analytical methods and propose a novel decomposition into dynamical, model truncation, short-periodic, and numerical error components. The first three are attributable to dis...

Reliable and efficient uncertainty propagation is crucial for the task of monitoring possible impacts of Near Earth Asteroids with our planet. It is well known that a switch of the primary body can greatly reduce the numerical truncation error in the case of planetary flybys. In the present work, the advantages of performing a primary body switch i...

This book discusses the design of new space missions and their use for a better understanding of the dynamical behaviour of solar system bodies, which is an active ﬁeld of astrodynamics. Space missions gather data and observations that enable new breakthroughs in our understanding of the origin, evolution and future of our solar system and Earth’s...

We propose a method to account for the Earth oblateness effect in preliminary orbit determination of satellites in low orbits with radar observations. This method is an improvement of the one described in Gronchi et al (2015b), which uses a pure Keplerian dynamical model. Since the effect of the Earth oblateness is strong at low altitudes, its incl...

We present an efficient strategy for the numerical propagation of small Solar System objects undergoing close encounters with massive bodies. The trajectory is split in severalphases, each of them being the solution of a perturbed two-body problem. Formulations regularized with respect to different primaries are employed in two subsequent phases. I...

The modern optical telescopes produce a huge number of asteroid observations, that are grouped into very short arcs (VSAs), each containing a few observations of the same object in one single night. To decide whether two VSAs, collected in different nights, refer to the same observed object we can attempt to compute an orbit with the observations o...

The accurate computation of interplanetary trajectories is a challenging task when close encounters with major bodies are involved. In this paper, we investigate the possibility of reducing global numerical error by employing regularized formulations of orbital dynamics and element methods, such those belonging to the Dromo family. Results show tha...

Close encounters with major Solar System bodies may bring about a strong amplification of numerical error during inter-planetary orbit propagation. In this work, we reduce global numerical error by integrating regularized equations of motion instead of the classical Newtonian equations in Cartesian coordinates. The integration performance of severa...

With the improvements of the observational technology for the new surveys the number of asteroid detections is rapidly increasing. For this reason we must use very efficient methods to compute orbits with these data. We have to identify observations taken in different nights as belonging to the same asteroid. If we do not have an efficient algorith...

Seven spatial elements and a time element are proposed as the state variables of a new special perturbation method for the two-body problem. The new elements hold for zero eccentricity and inclination and for negative values of the total energy. They are developed by combining a spatial transformation into projective coordinates (as in the Burdet–F...

We present the results of our investigation on the use of the two-body
integrals to compute preliminary orbits by linking too short arcs of
observations of celestial bodies. This work introduces a significant
improvement with respect to the previous papers on the same subject (see
Gronchi et al. 2010, 2011). Here we find a univariate polynomial equ...

We propose two time elements for the orbit propagator named Dromo. One is linear and the other constant with respect to the independent variable, which coincides with the osculating true anomaly in the Keplerian motion. They are defined from a generalized Kepler's equation written for negative values of the total energy and, unlike the few existing...

A formulation of the perturbed two-body problem that relies on a new
set of orbital elements is presented. The proposed method represents
a generalization of the special perturbation method published by Peláez
et al. in 2007 for the case of a perturbing force that is partially
or totally derivable from a potential. We accomplish this result by
empl...

A formulation of the perturbed two-body problem that relies on a new set of seven orbital elements and a time-element is presented. The proposed method generalizes the special perturbation method published by Peláez et al. in 2007 for the case of a perturbing force that is partially or totally derivable from a potential. We accomplish this result b...

We present analytical formulas to estimate the variation of achieved deflection for an Earth-impacting asteroid following a continuous tangential low-thrust deflection strategy. Relatively simple analytical expressions are obtained with the aid of asymptotic theory and the use of Peláez orbital elements set, an approach that is particularly suitabl...

Two extensions of the fast and accurate special perturbation method recently developed by Peláez et al. are presented for elliptic motion. A comparison with Peláez's method and with the very efficient Stiefel-Scheifele's method, for the problems of oblate Earth plus Moon and continuous radial thrust, shows that the new formulations can appreciably...

The special perturbation method DROMO developed by Peláez in 2006 for the perturbed two-body problem is employed to propagate the relative motion in spacecraft formation flying, and the performance of the new method, named DROMO-FF, is analyzed. DROMO is a very fast and accurate regularized method which involves a set of seven integrals of the pure...

A classical approach to the many-body problem is that of using special perturbation methods. Nowadays and due to the availability of high-speed computers is an essential tool in Space Dynamics which exhibits a great advantage: it is applicable to any orbit involving any number of bodies and all sorts of astrodynamical problems, especially when thes...

An analytical solution of the two body problem perturbed by a constant tangential acceleration is derived with the aid of
perturbation theory. The solution, which is valid for circular and elliptic orbits with generic eccentricity, describes the
instantaneous time variation of all orbital elements. A comparison with high-accuracy numerical results...

A new formulation of the spacecraft relative motion for a generic orbit is presented based on the orbital propagation method proposed by Peláez et al. in 2006 [1]. Two models have been developed. In the first model the method is applied to each spacecraft using a time synchronization of the system dynamical states. In the second model we employ a l...

## Projects

Projects (4)

The aim of the Training School is to present a contemporary review of recent results in the field of Celestial Mechanics. Special emphasis will be placed on the theoretical aspects.
REGISTRATION DEADLINE: OCTOBER 30, 2019
See our webpage:
http://www.mat.unimi.it/I-CELMECH/index.php/training-school/

We wish to develop an efficient algorithm which is able to predict the possible collisions between any two space debris of the current catalogue.